1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * 	Format of an ARP firewall descriptor
4 *
5 * 	src, tgt, src_mask, tgt_mask, arpop, arpop_mask are always stored in
6 *	network byte order.
7 * 	flags are stored in host byte order (of course).
8 */
9#ifndef _ARPTABLES_H
10#define _ARPTABLES_H
11
12#include <linux/if.h>
13#include <linux/in.h>
14#include <linux/if_arp.h>
15#include <linux/skbuff.h>
16#include <uapi/linux/netfilter_arp/arp_tables.h>
17
18/* Standard entry. */
19struct arpt_standard {
20	struct arpt_entry entry;
21	struct xt_standard_target target;
22};
23
24struct arpt_error {
25	struct arpt_entry entry;
26	struct xt_error_target target;
27};
28
29#define ARPT_ENTRY_INIT(__size)						       \
30{									       \
31	.target_offset	= sizeof(struct arpt_entry),			       \
32	.next_offset	= (__size),					       \
33}
34
35#define ARPT_STANDARD_INIT(__verdict)					       \
36{									       \
37	.entry		= ARPT_ENTRY_INIT(sizeof(struct arpt_standard)),       \
38	.target		= XT_TARGET_INIT(XT_STANDARD_TARGET,		       \
39					 sizeof(struct xt_standard_target)), \
40	.target.verdict	= -(__verdict) - 1,				       \
41}
42
43#define ARPT_ERROR_INIT							       \
44{									       \
45	.entry		= ARPT_ENTRY_INIT(sizeof(struct arpt_error)),	       \
46	.target		= XT_TARGET_INIT(XT_ERROR_TARGET,		       \
47					 sizeof(struct xt_error_target)),      \
48	.target.errorname = "ERROR",					       \
49}
50
51extern void *arpt_alloc_initial_table(const struct xt_table *);
52int arpt_register_table(struct net *net, const struct xt_table *table,
53			const struct arpt_replace *repl,
54			const struct nf_hook_ops *ops);
55void arpt_unregister_table(struct net *net, const char *name);
56void arpt_unregister_table_pre_exit(struct net *net, const char *name);
57extern unsigned int arpt_do_table(void *priv, struct sk_buff *skb,
58				  const struct nf_hook_state *state);
59
60#ifdef CONFIG_NETFILTER_XTABLES_COMPAT
61#include <net/compat.h>
62
63struct compat_arpt_entry {
64	struct arpt_arp arp;
65	__u16 target_offset;
66	__u16 next_offset;
67	compat_uint_t comefrom;
68	struct compat_xt_counters counters;
69	unsigned char elems[];
70};
71
72static inline struct xt_entry_target *
73compat_arpt_get_target(struct compat_arpt_entry *e)
74{
75	return (void *)e + e->target_offset;
76}
77
78#endif /* CONFIG_COMPAT */
79#endif /* _ARPTABLES_H */
80